FREMONT, Ohio -- Authorities are searching for a gunman who opened fire in a northern Ohio nightclub early Sunday. WTOL in Toledo reports three people were killed and another was seriously injured.

Witness at the Last Call Saloon said an argument led to the shooting. A bartender, customer and off-duty Elmore police officer were killed. Updates on the fourth victim’s injuries are not yet known.

Fremont Mayor Jim Ellis released the following statement:

"As we have seen too often in recent years, thoughtless violence can and does occur in any community in our nation. Most often all that can be done is to mourn the loss of life, find and prosecute the perpetrators and pray for healing of the community's spirit. We will do all of these things as we offer help to the families of the victims, our neighbors, and keep them in our hearts. We will face this challenge head on and with unflagging diligence."